District K-12 enrollment Less than 250 250-999 1,000-1,999 2,000-4,999 5,000-9,999 10,000 or more

0.92 1.11 1.35 1.26 1.42 0.67

0.49 0.76 1.20 0.85 1.21 0.71

1.04 1.31 1.70 1.23 1.95 0.86

Percent of K-12 students in district who were approved for free or reduced-price lunches 0-34 35-49 50-74 75 or more District did not participate in free or reduced-price lunch program

0.87 1.08 1.06 0.78

0.64 1.00 0.69 1.20

0.93 1.35 1.22 1.48

2.88

4.77

5.82

Table A-11. Standard errors for Table 11: Among districts with more than one school, percentage distribution of public school districts, by specific agreements with Table A-11. principals' associations or unions and selected public school district characteristics: 2007-08

Selected public school

Percentage distribution of districts that had a specific agreement with a principals' association or union

SOURCE: U.S. Department of Education, National Center for Education Statistics, Schools and Staffing Survey (SASS), "Public School District Data File," 2007-08.